This study investigated the use of an electronegative (hydrophillic) self-assembled monolayer (SAM) as a coating on a stiff insertion shuttle to carry a polymer probe into the cerebral cortex, and then the detachment of the shuttle from the probe by altering the shuttle's hydrophobicity.

Used 11-mercaptoundecanoic acid.

Cr/Au (of course) evaporated on 15um thick Si shuttle.

SAM attracts water once inserted, causing the hydrophobic polymer to move away.

Why not make the polymer hydrophillic?

Is this just soap?

Used agarose brain model.

Good list of references for the justification of soft electrodes, and researched means for addressing this, mostly usnig polymer stiffeners.

"However, polymer probes stick to metallic and silicon surfaces through hydrophobic interactions, causing the polymer probe to be carried out of the brain when the insertion shuttle is removed. The solution is to use a highly hydrophillic, electronegative, self-assembled monolayer coating on the shuttle.

Biran et al 2005 suggests that incremental damage due to stab wounds from the shuttle (needle) should be minor.